WLFINKMO Manifold Engine Block Drain Plug Kit Replaces Sierra 18-4226 for Mercruiser 22-806608a02 Compatible with GLM 13992 Pack of 5

Says it’s for a 4.3 mercruiser - but the diameter is too small.

They are typical Amazon Chinese aftermarket parts but they work. Probably won't last as long as the Quicksilver or Merc manufactures ones. You might get by with replacing "O" rings on your old ones. I did find out I has some leaking when I replaced them.

An important and inexpensive maintenance replacement for your boat motor. They can dry out, crack and break off. Replacing every few years will alleviate the need to ream a broken plug out. Also, the fresh o ring will keep it from dripping or leaking.

China made and seem to be ok. same as OEM, 1/2-13 thread pitch with O rings.

They may be an aftermarket part, but I couldn't tell the difference between them and the OEM plugs they replaced.